patch [#30620] Wiki Quick Hack: Make Tooltip Text Colour Themeable

from luke frisken (lfrisken), with some edits.

some tooltip colors weren't visible with different backgrounds, now the base tooltip color is used and tinted for python/alert/shortcuts etc. the tint colors are still hard coded.

release/scripts/templates/ui_panel_simple.py

@@ -2,6 +2,7 @@ import bpy
 
 
 class HelloWorldPanel(bpy.types.Panel):
+    """Creates a Panel in the Object properties window"""
     bl_label = "Hello World Panel"
     bl_idname = "OBJECT_PT_hello"
     bl_space_type = "PROPERTIES"